Draw-in wires for this purpose usually include a part with a holding apparatus attached to the tip for the lines to be drawn in. They are not very suitable for more complex tube systems with changing tube parameters such as changes in the diameter or the direction because they need to have a certain stability on the one hand so that they can also be pushed easily through longer tube systems and a certain flexibility on the other hand so that they will not get stuck in tighter curves, which cannot be achieved by an integral configuration. The draw-in wires as disclosed in WO 2006/027400 A1, U.S. Pat. No. 3,110,478 A1 and EP 1 058 361 A1 are all characterized in that the described frame is supplemented by a draw-in wire tip, the tip allegedly representing an improvement by an increase in the flexibility. Nevertheless, easy drawing into more complex tube systems is not ensured.
It is known from U.S. Pat. No. 6,182,432 B to provide a draw-in wire tip of reduced stiffness for facilitating the insertion of the draw-in wire. The specification alternatively proposes to provide the draw-in wire itself in its front region with increased flexibility. This configuration allows inserting the draw-in wire in a comparatively easy manner even under unfavorable conditions. Nevertheless, this solution is not satisfactory because the production of a draw-in wire with continuously decreasing stiffness is complex and a weak point is provided in the tip region by the reduced cross section which prevents the transmission of high tensile forces when drawing in cables or the like.